Caption: Paediatric heart transplant surgery. The vital heart/lung machine, used to maintain "hypothermic cardio-pulmonary by-pass" throughout the transplant, is seen in foreground. Prior to surgery, the patient, a boy aged 6 weeks, had his body temperature cooled to 15 degrees C. This was achieved using ice packs on his head & by cooling his blood as it flowed through the heart/lung machine. The actual transplant surgery was completed in less than one hour, with the surgeon working without the aid of a microscope or magnifying loupes. Finally, the infant's body temperature was gradually restored to normal & his new heart induced to beat.